This invention relates to photopolymeric images inlaid into solid synthetic rock-like structures. More specifically, this invention relates to a photopolymeric image or design which is inlaid into a solid matrix of a synthetic rock-like structure consisting of a filler in a thermosetting resin.
It has been known to produce decorative plaques, plates and the like, wherein an image, writing, picture, or similar material have been applied to a solid substrate such as marble, granite, or a synthetic rock-like substance in the form of a decal or overlay. Such products are not durable and will scratch, or the surface wear away.
It has now been discovered that an actual inlay into a solid synthetic rock-like substance can be produced from any image which is capable of being photographed.
Photosensitive polymers are well known in the art for use as printing plates. These plates generally consist of a flexible backing coated with a photosensitive polymer which may be a gelatin, albumen, gum arabic, glue or similar substance. Plates of later origin and preferred herein consist primarily of an emulsion of a polyvinyl alcohol or polyvinyl acetate or mixtures of the two along with a plasticizer such as dibutyl phthalate. These polymeric mixtures are sensitized to light by the addition of a light sensitizing agent such as a dichromate salt or a diazonium compound. These photosensitive polymeric printing plates are well-known and typical plates are described in patents such as U.S. Pat. Nos. 163,514; 473,753; 2,174,629; 2,709,654; 3,189,451 and 3,280,734 and British Pat. No. 1,334,464. Since photopolymeric plates are well known in the art a detailed discussion of their properties is not considered necessary. Basically, these plates are exposed to a negative and the portion of the photopolymeric plate exposed to the light becomes hardened or rendered insoluble by the sensitizing agent. The plate is then developed by washing away the unexposed portions with a solvent which may be either an organic or aqueous solvent depending upon the chemical composition of the plate used. The non-sensitized portion of the plate is dissolved leaving a relief image attached to the flexible backing which can then be used as a printing plate.
In the present invention these plates are used in an entirely different manner. Especially preferred are the plates disclosed in the above mentioned British Pat. No. 1,334,464. These plates consist of a polyvinyl acetate base containing minor amounts by weight of polyvinyl alcohol, dibutyl phthalate plasticizer, a blue dye and a dichromate salt sensitizer.
According to the present invention, it has been discovered that photopolymeric printing plates can be imbedded into a synthetic rock-like structure and the flexible backing of the printing plate removed thereby producing a solid rock-like structure having imbedded therein the photopolymeric image. This product, and the process of making the same, are both considered to be novel and will be described in detail herein.